1. Field of the Invention
The present invention relates generally to electronic connector systems and, more specifically, to low-profile connector systems for user-removable electronic modules, such as transceiver modules that interface with a peripheral device port of a portable computer.
2. Description of the Related Art
Electrical connectors are used to interconnect circuit cards and other electronic modules or assemblies. A connector commonly used in personal computer systems is known as a D-shell connector because the contact pins of the male connector and female connector are enclosed within generally D-shaped structures that mate to promote a secure mechanical connection as well as provide electromagnetic shielding. In a D-shell connector, contact pins of the male connector are frictionally received in contact holes of the female connector. The wiping action between the pins and holes minimizes the buildup of oxides or dirt that could impede electrical conduction. Connectors that have wiping mating parts define one of a number of general categories of connectors.
Another general category of connectors is defined by those connectors that have abutting mating parts. One such connector, illustrated in FIG. 1A, is known as the J-lead connector (10) because the electrical contacts 12 are generally J-shaped. A J-lead connector 10 is typically used to interconnect two circuit cards 14 and 16 that are disposed in a back-to-back orientation. The J-lead connector 10 is mounted on one of the circuit cards, typically by soldering one end of each contact 12 to a surface-mount pad (not shown) on the circuit card. The shape of contacts 12 provides some resiliency or springiness, and when circuit cards 14 and 16 are brought together, as illustrated in FIG. 1B, pads (not shown) on circuit card 16 make electrical and mechanical contact with contacts 12 of circuit card 16. Contacts 12 are deflected slightly, and the spring force exerted by the deflected contacts 12 against the contact pads promotes good electrical connection.
Various international and industry standards define the type of connectors used to interface personal computers to external communication devices such as modems, network interfaces, and other transceivers. A well-known type of transceiver developed by an industry consortium and known as a gigabit interface converter (GBIC) or serial optical converter (SOC) provides an interface between a computer and an Ethernet, Fibre Channel or other data communication environment. The D-shell connectors of such transceivers mate with a complementary D-shell connector mounted on the circuit card of the host computer.
It is desirable to miniaturize transceivers in order to increase the port density associated with the network connection (switch boxes, cabling patch panels, wiring closets, computer I/O, etc.). Various standards are known that define form factors for miniaturized electronic devices, such as the Small Form Factor (SFF) standard, which specifies an enclosure 9.8 mm in height by 13.5 mm in width and having a minimum of 24 electrical input/output connections.
Miniaturizing a transceiver, however, raises a number of potential connector problems. Among these problems is mechanically coupling the connectors in a manner that biases the contacts of one connector against those of the mating connector to provide a secure electrical connection. Another problem is releasing the connectors from one another in a manner that is convenient to the user and that minimizes stress on the electrical contacts. Still another problem relates to aligning the contacts of one connector with respect to those of the mating connector. These problems and deficiencies are satisfied by the present invention in the manner described below.
The present invention relates to an electrical connector system having two connectors in which one of the connectors is included in a module mateable with the other connector in a pluggable manner. The other connector includes a body and two or more electrical contacts. In accordance with one aspect of the invention, the body of that electrical connector includes a spring that provides a combined lock-down force and kick-out force. The lock-down force biases the module against the other connector, thereby providing a secure electrical and mechanical connection. The kick-out force biases the module away from the other connector to separate or eject the module when a user actuates a release mechanism. In accordance with another aspect of the invention, the module includes a slot that engages a projection on the other connector to promote alignment of the mating electrical contacts.
The body of module connector is definable by three mutually perpendicular axes and has a connector block. The body, including the connector block, has a very low profile, and in certain exemplary embodiments it is preferably less than about 10 mm in height, i.e., the dimension defined by the third axis, to accommodate the Small Form Factor standard and to facilitate surface-mounting the bottom of the body on a circuit board. The connector block retains the contacts, which are spaced from one another in the direction of the first axis. One of the connectors includes a guide rail to facilitate mechanical mating of the connectors. In an exemplary embodiment, the connector block is at one end of the guide rail, which is elongated between a first end and second end of the body along the first axis. One of the connectors also includes a camming element that, in response to a force of a mating connector being moved along the first axis, redirects the force in a direction having a component along the third axis so as to cause relative motion and resulting electrical contact between the contacts of the electrical connector and the contacts of the mating connector. In an exemplary embodiment, the camming element is a cam on the connector block having two oppositely inclined ramp sections. When a mating connector having complementary contacts is, guided by the guide member, moved into initial engagement with the cam, the first ramp lifts the mating connector, including its contacts, above the connector block. When the mating connector is moved further into engagement with the cam, the second ramp lowers the mating connector onto the connector block, with the contacts of the mating connector lowering onto and making contact with the contacts of the electrical connector. The camming motion minimizes wiping between the mating contacts. In addition, the contacts of the electrical connector are preferably somewhat resiliently deflectable to promote good electrical contact.
The electrical contacts may be arrayed in two or more rows, each parallel to the second axis and having two or more contacts.
In an exemplary embodiment, the mating electrical connector that mates with the electrical connector having the body and connector block is included in an optical transceiver module. Nevertheless, the connector system may be used in other arrangements and to couple other types of electronic modules or assemblies.
The foregoing, together with other features and advantages of the present invention, will become more apparent when referring to the following specification, claims, and accompanying drawings.